I'm fairly new to knitting, and I'm attempting my first non-linear (aka not a scarf) thing, by knitting a sweater for one of my dogs. I'm following the pattern here (tried to post the link, but wasn't able to...only including relevant part of pattern): Neck

Repeat m1 increase on each edge of RS rows as established 10 times, sl 1, and k last st to maintain selvedges.
Continue to work the rib sts as established. When increases are complete you will have 70[84] sts.

Work pattern as established until piece measures 4.5[6] inches from beginning, ending with a WS row.
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I'm in the first body shaping phase of this project. I'm a little confused, first of all, why you don't increase on both ends as you do in the first RS row (see Row 3 instructions). Is this just a typo? Also, I'm a little confused at what the pattern means by "Repeat m1 increase on each edge of RS rows as established 10 times, sl 1, and k last st to maintain selvedges." I get that I'm supposed to increase (at both ends?) for each RS row, and that I need to slip the first stitch and knit the last stitch, but how do I go about doing that? Because the instructions for both of the RS rows in this section are slightly different (especially towards the ends). This may seem like a dumb question, but any help any of you can provide would be great. Thanks!

Yes, I think you're right, increase at both ends on the RS rows. There's a missing increase near the end of row 3 in the instructions. Usually these patterns are symmetrical and so the row should end with a knit to the last 2sts, m1, k2. Then the instruction to repeat increase on each edge of RS rows makes sense. Since you've already increased 4 sts however, you'll only need to repeat the increase 9 times in order to get to the 22st increase from the cast on (48sts + 22sts=70sts for the smaller size).
You'll slip the first st of the row in order to make a clean chain on the edges which will look neater than working both the first st and the last st of the row. The RS rows end in a knit st, so knit that last st.

Thank you so much! So based on Row 1 and Row 3, the m1 should be the 3rd stitch in from either side. I'm also not sure how to finish up the edges on the WS rows. The "edges" (the pattern before and after the "work as they appear" portion) of Rows 2 and 4 are different. I guess I'm not intuitive enough with my knitting to know what would be the right thing to do for the next several rows.